Mower unit

ABSTRACT

A mower unit includes a mower deck, a plurality of blades mounted inside the mower deck and rotatable about vertical shafts supported to the mower deck, the mower deck defining, on one lateral side thereof, a discharge outlet for discharging cut grass cut by the plurality of blades, and an opening and closing member configured to be movable to a closing position for closing the discharge outlet and also to an opening position away from the discharge outlet for opening the discharge outlet, the opening and closing member at the opening position being disposed along an outer face of the mower deck.

BACKGROUND OF THE INVENTION

The present invention relates to a mower unit.

As a prior art pertinent thereto, as disclosed in JP2003-125626 forinstance, there is known a mower capable, with attachment/detachment ofa blowout preventing plate, of selectively providing a mulching mode inwhich cut grass cut by rotary blades are caused to stay within a mowerdeck to shredded into further smaller pieces and a side discharge modein which the cut grass cut by the rotary blades are discharged as theyare from a lateral side of the mower deck. Further, as disclosed in JP2005-253387, there is also known a mower capable, withattachment/detachment of a shredding baffle, of selectively providing amulching mode in which cut grass cut by rotary blades are caused to staywithin a mower deck to be shredded into further smaller pieces and aside discharge mode in which the cut grass cut by the rotary blades isdischarged from a lateral side of the mower deck.

With such constructions as above employed by the conventional mowersdisclosed in the above-identified documents involving attachment anddetachment of a blowout preventing plate or a shredding baffle, whene.g. a side-discharge mode of operation was to be effected, it wasneeded to store the blowout preventing plate or shredding baffledetached from the mower deck at a driver's seat of the lawn mower or ina storage vault. Therefore, if the mode of operation was to be switchedover from the side-discharge mode to the mulching mode, it was necessaryto carry the blowout preventing plate or shredding baffle stored at thedriver's seat or the storage vault to the mower. Hence, the switchoverof the operation mode could not be done speedily on the work site andthe attachment and detachment of the blowout preventing plate orshredding baffle could not be done in an efficient manner. Further, ifthe blowout preventing plate or shredding baffle was stored in a storagevault or the like, there was also a risk of this blowout preventingplate or shredding baffle getting lost.

SUMMARY OF THE INVENTION

An object of the present invention is to realize a mower unit whichfacilitates the switchover of the operation mode between the mulchingmode and the side-discharge mode and which also can effectively preventloss of an opening and closing member.

For accomplishing the above object, a mower unit, according to thepresent invention, comprises:

a mower deck;

a plurality of blades mounted inside said mower deck and rotatable aboutvertical shafts supported to said mower deck, said mower deck defining,on one lateral side thereof, a discharge outlet for discharging cutgrass cut by the plurality of blades; and

an opening and closing member configured to be moved to a closingposition for closing said discharge outlet and also to an openingposition away from said discharge outlet for opening this dischargeoutlet, said opening and closing member at said opening position extendsalong an outer face of said mower deck.

With the above-described construction, as there is provided theopening/closing member configured to be movable to a closing positionfor closing the discharge outlet and also to an opening position awayfrom the discharge outlet for opening this discharge outlet, by movingthis opening and closing member, the discharge opening can be closed andopened, thus effecting the operation mode switchover between themulching mode (the opening and closing member is set at the closingposition) and the side-discharge mode (the opening and closing member isset at the opening position). That is, the operation mode switchover canbe realized by moving the opening and closing member between the closingposition and the opening position. Therefore, in the side-dischargemode, the opening and closing member can be stored as being keptattached to the mower deck, without needing to be stored at the driver'sseat or in a storage vault.

Further, when at its opening position, the opening and closing member isdisposed along the outer face of the mower deck. With this, the openingand closing member, at its opening position, can be disposed withoutsignificantly projecting from the outer face of the mower deck.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall left side view of a riding lawn mower,

FIG. 2 is an overall plan view of the mower in a mulching mode,

FIG. 3 is a plan view in horizontal section showing the mower in themulching mode,

FIG. 4 is a plan view showing a right portion of the mower in themulching mode,

FIG. 5 is a plan view showing the right portion of the mower in aside-discharge mode,

FIG. 6 is a right side view of the mower in the mulching mode,

FIG. 7 is a right side view of the mower in the side-discharge mode,

FIG. 8 is a rear view in vertical section showing the right portion ofthe mower in the mulching mode,

FIG. 9 is a rear view in vertical section showing the right portion ofthe mower in the side-discharge mode,

FIG. 10 is a perspective view for explaining an opening and closingconstruction of a pivotal cover,

FIG. 11 is a perspective view for explaining a construction of a linkmechanism,

FIG. 12 is a perspective view for explaining an opening and closingconstruction of an engine hood,

FIG. 13 is a front view in vertical section for explaining the openingand closing construction of the engine hood,

FIG. 14 is a side view in vertical section for explaining the openingclosing construction of the engine hood,

FIG. 15 is a schematic side view in vertical section for explaining alock mechanism of an HST pedal,

FIG. 16 is an overall left side view of the riding lawn mower with agrass collector attached thereto,

FIG. 17 is a plan view of the right portion of the mower in a cut grasscollecting mode, and

FIG. 18 is a right side view of the mower in the cut grass collectingmode.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Next, embodiments of the invention will be described with reference tothe accompanying drawings. While a plurality of embodiments will bedescribed below, it is understood that various combinations of featuresof one embodiment and features of another embodiment too are included inthe scope of the present invention.

[General Construction of Riding Lawn Mower]

With reference to FIGS. 1 through 3, a general construction of a ridinglawn mower will be described As shown in FIG. 1, in this riding lawnmower, a traveling vehicle body 3 includes steerable front wheels 1 andnon-steerable, but drivable rear wheels 2. From the bottom face of thistraveling vehicle body 3, there is suspended a mower unit M via a linkmechanism 4 to be lifted up and down in translation. The travelingvehicle body 3 mounts, at a front portion thereof, a vertical shaft typeengine 5. An output shaft 6 projects from a lower portion of this engine5. A vertical shaft rotational power obtained from this output shaft istransmitted via a belt to a transmission case 27 mounting the rearwheels 2 and the mower unit M, respectively.

As shown in FIGS. 2 and 3, the mower unit M has a twin-bladeconstruction including two rotary blades 8, 9 mounted on a mower deck 7,with the blades 8, 9 being juxtaposed in the right and left direction.The rotary blades 8, 9 are connected to lower ends of drive shafts 10,11 which are mounted through the upper face of the mower deck 7 at rightand left portions thereof, respectively (each of the rotary blades 8, 9comprises a band plate like steel member having a cutter blade 8 a, 9 aat one of opposed ends thereof and a wind-raising blade 9 b, 8 b formedas a bent portion at the other end thereof.

At a position rearwardly of a right and left center of the upper face ofthe mower deck 7, there is provided an input shaft 12. A drive belt 15is entrained in tension about an input pulley 13 attached to the inputshaft 12 and an output pulley 14 attached to the output shaft 6 of theengine 5. Further, a single transmission belt 21 is entrained in tensionabout a drive pulley 16 attached to the input shaft 12, transmissionpulleys 17, 18 attached to the respective drive shafts 10, 11 and guidepulleys 19,19 and a tension pulley 20 mounted to the mower deck 7, sothat the two rotary blades 8, 9 are driven to rotate in oppositedirections to each other. The rotational directions of the two rotaryblades 8, 9 are set such that rearwardly of rotational axes P1, P2thereof relative to the vehicle body, rotary paths of the leading endsof the two rotary blades 8, 9 are inwardly opposed to each other.

The mower unit M is disposed with a slight inclination such that therotational axis P1 of the rotary blade 8 disposed on the left side ofthe vehicle body as viewed from above may be located forwardly of therotational axis P2 of the rotary blade 9 disposed on the right side ofthe vehicle body, and as the rotary paths of the leading ends of the tworotary blades 8, 9 are slightly overlapped with each other in the foreand aft direction so as to restrict occurrence of cutting leftover(cutting failure) between the two rotary blades 8) 9.

At the front center portion and the rear center portion of the inside ofthe mower deck 7, there are mounted a front vacuum plate 22 and a rearvacuum plate 23, each of which as an angle shape in its plan view. And,along the rotary paths of the leading ends of the rotary blades 8, 9,there are formed approximately circular cutting chambers 24, 25 for therotary blades 8, 9, respectively. The tops of the front vacuum plate 22and the rear vacuum plate 23 are opposed to each other with a gaptherebetween, and an opening 26 for allowing flowing passage of cutgrass is formed between the two cutting chambers 24, 25.

The mower deck 7 has an elliptical shape in its plan view, whichexhibits also a bowl-like curved shape in its cross section. The mowerdeck 7 is formed by pressing of a steel plate into such a shape that ina mulching mode to be described later, cut grass cut by the rotaryblades 8, 9 are allowed to stay within the mower deck 7 to be shreddedinto even smaller pieces, the shape also ensuring sufficient strengthfor this mower deck 7.

An edge portion 7 a at the lower end of the mower deck 7 is bent to theouter side and also to the upper side along the entire peripherythereof, except for a lower portion of a discharge outlet 7 b to bedescribed later, so that the portion is formed integrally in a U-shapecross section which is open upward, thus ensuring sufficient strength atthe lower end of the mower deck 7. The lower edge 7 a located downwardlyof the discharge outlet 7 b is formed integrally with the mower deck 7and has an L-shaped cross section, so that this edge portion 7 a isconfigured so as not to provide much resistance to the dischargingoperation of the cut grass.

To the lower side of the edge portion 7 a of the mower deck 7, there isdetachably fixed a band-like reinforcing plate 28 conformed with theedge portion 7 a of the mower deck 7. With this, it is possible toprevent damage in the edge portion 7 a of the mower deck 7 due tocontact with a rock or the like when the riding lawn mower travels withthe mower unit M being lowered and possible also to improve the strengthof the edge portion 7 a of the mower deck 7 and to allow replacement ofthe reinforcing plate 28 when damaged.

As shown in FIG. 3, on the opposite side away from the cutter blades 8a, 9 a of the rotary blades 8, 9, there are formed cutout portions 8 c,9 c. These cutout portions 8 c, 9 c allow reduction in the weight at theleading end portions of the rotary blades 8, 9, thus restrictingrotational torques of the rotary blades 8, 9. Further, with theformation of these cutout portions 8 c, 9 e, the upward bendingoperation for forming the wind-raising blades 8 b, 9 b can be carriedout easily and the manufacture costs of the rotary blades 8, 9 can bereduced, as well.

The cutout portions 8 c, 9 c are shaped so as to extend progressivelywinder in the rotational direction toward the leading ends thereof, andat the opposed ends thereof there are formed curved portions 8 d, 9 d.With the above-described formation of the cutout portions 8 c, 8 c andthe tapered shaping of the leading ends of the rotary blades 8, 9, it ispossible to prevent occurrence of stress concentration in the rotaryblades 8, 9. As a result, the rotational torques of the rotary blades 8,9 are restricted and the manufacture cost of the rotary blades 8, 9 isrestricted, and at the same time the damage of these rotary blades 8, 9can be prevented.

[Detailed Construction of Pivotal Cover]

With reference to FIGS. 4, 5 and 8-10, the detailed construction of apivotal cover 30 (corresponding to “a guide member”) will be described.As shown in FIGS. 4 and 5, on the right side portion of the mower deck7, there is attached the pivotal cover 30 to be vertically pivotableabout an axis P3 oriented along the fore and aft direction. Inoperation, in a side-discharge mode to be described later, when thevehicle travels with this pivotal cover 30 being pivoted downward andthe rotary blades 8, 9 being rotated, grass pieces cut inside the mowerdeck 7 can be discharged rearward in an obliquely right directionrelative to the mower deck 7.

As shown in FIG. 8 and FIG. 9, the pivotal cover 30 is switchable in itsposture between a raised posture where the cover 30 is pivotally upwardabout the fore-and-aft axis P3 and a collapsed posture where the cover30 is pivoted downward about the fore-and-aft axis P3 to be collapsedalong the traveling surface. As illustrated in FIG. 4, in the raisedposture, the right-side outer end of the pivotal cover 30 is positionedon the more inner side than the right-side outer end of the mower deck7, so that the pivotal cover 30, in the raised posture, does not projectto the outer side of the mower deck 7 in the plan view.

As shown in FIG. 4, FIG. 5 and FIGS. 8- 10, the pivotal cover 30 isformed by bending a flat plate into a downwardly open angular hook shapein the cross section along the fore and aft direction. So that, in thecollapsed posture, the lower portion of the pivotal cover 30, andconnecting portion 30 a and a discharge portion 30 b are open,respectively. The connecting portion 30 a of the pivotal cover 30 forits connection with the mower deck 7 is formed linear in the collapsedposture in the plan view and its cross sectional shape is a downwardlyopen angular hook shape curved in conformity with the shape of thedischarge outlet 7 b of the mower deck 7. The discharge portion 30 b ofthe pivotal cover 30 is shaped convex on the outer side in the collapsedposture in the plan view and its cross sectional shape is a downwardlyopen angular hook shape.

In its collapsed posture, the pivotal cover 30 exhibits a shape of a fanextending wider from the connecting portion 30 a on the inner sidethereof toward the discharge portion 30 b on the outer side thereof, soas to allow discharge of cut grass in wide angle distribution. Further,in its rear view, the upper face of the pivotal cover 30 is inclineddownward obliquely outward, so as to restrict “swirling-up” of cut grassbeing discharged from the pivotal cover 30.

On the upper face of the pivotal cover 30, there are fixedly attachedfront and rear arms 31F, 31R. The front arm 31F includes a band-platelike arm body 31FA and a reinforcing member 31FB extending forwardlyfrom this arm body 31FA. The arm body 31FA and the reinforcing member31FB define attaching holes formed coaxially and communicated with eachother in the front and rear direction.

The rear arm 31R includes a band-plate like arm body 31RA and areinforcing member 31RB extending rearwardly from this arm body 31RA.The arm body 31RA and the reinforcing member 31RB define attaching holesformed coaxially and communicated with each other in the front and reardirection. At the lower portion of the leading end of the arm body 31RAof the arm 31R, there is formed an engaging portion 31RC for engagementwith a support member 33 cutout at its lower side as will be describedlater (see FIG. 8).

To an upper portion of the right side of the mower deck 7, there isaffixed a bracket 32 having an upwardly open angular hook shape. And, inits front and rear boss portions 32F, 32R bent upward, there are formedthrough holes along the front and rear direction. And, into these frontand rear through holes of the bracket 32 and the front and the attachingholes of the front and rear arms 31F, 31R, a pin 34 is inserted, so thatthe pivotal cover 30 is vertically pivotable about the axis P3 of thepin 34.

Between and across the front and rear arm bodies 31FA, 31RA, afore-and-aft frame in the form of a band plate is affixed. And, betweenthis fore-and-aft frame and the mower deck 7, there is provided atorsion spring 35. The pivotal cover 30 is pressed downward by an urgingforce of this torsion spring 35, so that vertical displacement of thepivotal cover 30 due to e.g. traveling of the riding lawn mower may berestricted.

With the above-described construction of the pivotal cover 30, when thepivotal cover 30 is pivoted downward, the dead weight of the pivotalcover 30 serves to retain this cover 30 in the lowered state, wherebythe grass pieces discharged from the discharge outlet 7 b of the mowerdeck 7 may be guided obliquely rearward to the right side of the ridinglawn mower.

[Detailed Construction of Slide Cover]

Next, with reference to FIGS. 4-9, the construction of a slide cover 37(corresponding to “an opening and closing member”) will be described indetails. As shown in FIG. 8 and FIG. 9, a pulley holder 38 is fixed byfastening to a blade attaching portion 7 c provided on the upper face ofthe mower deck 7. And, to this pulley holder 38, the drive shaft 11 isrotatably attached via a pair of upper and lower bearings 39. At thelower end of the drive shaft 11, there is fixed and fastened the rotaryblade 9, and at the upper end of the drive shaft 11, the transmissionpulley 18 is fixed as being fastened from the upper side thereof. Inoperation, as the transmission pulley 18 is rotated via the transmissionbelt 21, the rotary blade 9 is rotatably driven.

In the outer peripheral portion at the upper end of the pulley holder38, there is integrally formed a concave groove 38 a along the entireperiphery thereof. A body portion of a pivotal arm 40 having acylindrical body and a band-like arm member fixed thereto is fitted tothe pulley holder 38 from above and a ring-like stopper member 41 isfitted into the groove 38 a. With these, the pivotal arm 40 is attachedto the pulley holder 38 to be pivotable relative thereto, with itsvertical displacement being restricted, so that the pivotal arm 40 ispivoted in the front and rear direction about the axis P2 of the rotaryblade 9.

Such components as the pulley holder 38, the drive shaft 11, etc. arecovered by a curved conical guide plate 36. So that, in a mulching modeto be described later, cut grass blown up by the wind-raising blade 9 bprovided at the leading end of the rotary blade 9 may flow efficientlywithin the cutting chamber 25, thus preventing stagnation of the cutgrass in the vicinity of the pulley holder 38, the drive shaft 11, etc.,thus preventing interference with the flowing movement of the cut grass.

As shown in FIG. 4 and FIG. 5, the slide cover 37 is configured so as tobe able to cover the discharge outlet 7 b of the mower deck 7 from aboveover its entire surface and this shape of the cover is vertically curvedso as to conform with the shape of the mower deck 7.

As shown in FIG. 5, FIG. 8 and FIG. 9, at the upper end of the slidecover 37, a bracket 42 is fixedly attached. And, between and across thisbracket 42 and the pivotal arm 40 described above, there is provided aband-like plate spring 43. So that, via the pivotal arm 40 and the platespring 43, the slide cover 37 is supported to be pivotable in the frontand rear direction about the axis P2 of the rotary blade 9. In this way,the pivotal arm 40, the bracket 42, the plate spring 43, etc. togetherconstitute “a moving mechanism” for slidably moving the slide cover 37along the outer peripheral face of the mower deck 7 to a closingposition and also to an opening position.

When the slide cover 37 is not opened and closed, the slide cover 37,with its dead weight, is placed in contact with the outer peripheralface of the mower deck 7, and then as the slide cover 37 is manuallypushed up slightly, the plate spring 43 will be deformed to cause theslide cover 37 to leave the outer face of the mower deck 7, whereby theslide cover 37 can now be slid easy and smoothly.

The lower edge of the slide cover 37 is attached in such a manner as toextend along the above-described edge portion 7 a of the mower deck 7.With this, when the slide cover 37 is closed, leak of air inside themower deck 7 is effectively restricted and also the slide cover 37 canbe slid easily and smoothly along the edge portion 37 a of the mowerdeck 7.

At the upper portion of the slide cover 37 and on the lateral side ofthe bracket 42, a support member 33 is fixedly attached. This supportmember 33 consists of a vertical plate 33A fixed at its lower end to theslide cover 37 and a contact portion 33B formed as a bent portion fromthe upper end of the vertical plate 33A. When the slide cover 37 isclosed, the contact portion 33B is disposed downwardly of the rear arm31R affixed to the pivotal cover 30 in its raised posture.

At an end of the slide cover 37 on the outer side of the bracket 42,there is integrally formed an assist member 39 having an L-shapedvertical cross section, so that by pulling up a grip portion 39 a ofthis assist member 39, the slide cover 37 can be moved, thus improvingthe operability of the slide cover 37.

As shown in FIGS. 6 and 7, at the portion of the mower deck 7 on thefront and rear sides of the discharge outlet 7 b, there are fixedlyattached L-shaped hooks 44 each having an engaging hole 44 a. At thefront end of the slide over 37, there is fixedly attached a plate 45having a projection 45 a to be engaged with the engaging hole 44 a ofthe hook 44. And, at the rear end of the slide cover 37, there isfixedly attached a fixing member 46 having a pawl portion 46 a to beengaged with the L-shaped hook 44. In the opened condition of the slidecover 37 (the condition shown in FIG. 7), the slide cover 37 is closedto bring the projection 45 a of the plate 45 into engagement withengaging hole 44 a of the hook 44 so as to retain the front end of theslide cover 37. In this condition, the pawl portion 46 a of the fixingmember 46 will be engaged with the L-shaped hook 44 to push the controlportion 46 b of the fixing member 46 forwardly, whereby the slide cover37 can be fixed in the closed condition (the condition shown in FIG. 6).

As shown in FIG. 5, at an outer peripheral portion of the mower deck 7located at the left end of the slide cover 37 in its opened condition,there is also fixedly attached a hook 44 having the same shape as theabove-described hooks 44 provided at the front and rear ends of thedischarge outlet 7 b. In operation, when the slide cover 37 is opened,the pawl portion 46 a of the fixing member 46 located on the center rearside of the mower deck 7 will be engaged with the L-shaped hook 44 topush the control portion 46 b of the fixing member 46 to the right side,whereby the slide cover 37 can be fixed in the opened condition.

With the above-described construction of the slide cover 37, from thecondition where the discharge outlet 7 b is opened by the slide cover37, the fixing member 46 will be released and then the slide cover 37will be pulled up slightly by the assist member 39 to be slid to thefront side and the plate 45 will be engaged with the hook 44 and thefixing member 46 will be operated. With these, the discharge outlet 7 bcan be closed. Further, from the condition where the discharge outlet 7b is closed by the slide cover 37, the fixing member 46 will be releasedand the engagement between the plate 45 and the hook 44 will be releasedand the slide cover 37 will be pulled up slightly by the assist member39 to be slid to the rear side and the fixing member 46 will beoperated. With these, the discharge outlet 7 b can be opened.

[Operation Modes of Riding Lawn Mower]

Next, with reference to FIGS. 4-10, two operation modes which can berealized by this riding lawn mower will be described. As shown in FIG.4, FIG. 6, FIG. 8 and FIG. 10, when the pivotal cover 30 is pivotedupward to be switched over into the raised posture and the slide cover37 is slid forwardly to close the discharge outlet 7 b, the supportmember 33 fixed to the slide cover 37 is moved to the lower side of thearm 31R of the pivotal cover 30. Then, the side cover 37 is fixed to themower deck 7, thus realizing the mulching operation mode for allowingcut grass to stay inside the mower deck 7 to be shredded into furthersmaller pieces. Whereas, when the operator moves his or her hand awayfrom the pivotal cover 30, the engaging portion 31RC of the arm 31R willcome into contact with the contact portion 33B of the support member 33,so that the pivotal cover 30 is maintained in its raised posture. Inthis case, as the urging force of the torsion spring 35 is effective forpressing the engaging portion 31RC against the contact portion 33,looseness in the pivotal cover 30 can be prevented, hence, the pivotalcover 30 can be maintained in a stable manner. In this way, the supportmember 33 fixed to the slide cover 37 and the engaging portion 31RCformed in the arm 31R together constitute a retaining mechanism forretaining the slide cover 37 in its raised posture.

As shown in FIG. 5, FIG. 7, FIG. 9 and FIG. 10, when the slide cover 37is slid rearwards to open up the discharge outlet 7 b, the supportmember 33 fixed to the slide cover 37 is moved rearward, thus allowingdownward pivotal movement of the pivotal cover 30. And, the slide cover37 will be fixed to the mower deck 7, thus realizing the side-dischargeoperation mode for discharging cut grass to be discharged from theinside of the mower deck 7 to the right rear side of the vehicle body.Then, when the operator moves his or her hand away from the pivotalcover 30, the pivotal cover 30 will be switched over into the collapsedposture.

With the above-described constructions of the pivotal cover 30 and theslide cover 37 which allow realization of the mulching operation modeand the side-discharge operation mode, the switchover operation betweenthe two operation modes can be carried out easily and speedily.Moreover, the switchover operations between the mulching mode and theside-discharge mode can be effected, without needing to detach suchcomponents as the slide cover 37, the pivotal cover 30, etc. from themower deck 7. Furthermore, as the pivotal cover 30 is retained in itsraised posture, in the mulching mode, the pivotal cover 30 does notproject to the right outer side of the mower deck 7. Hence, in themulching operation mode, the total width of the mower unit M can berestricted, so that the mower deck 7 can be moved closer, on its rightand left sides, to a wall, adjacent lawn lane (lance adjacent cut lawnlane) to effect a lawn mowing operation, without occurrence of cuttingleftover (cutting failure).

[Detailed Construction of Link Mechanism]

Next, with reference to FIG. 1 and FIG. 11, the construction of the linkmechanism 4 will be described in details. As shown in FIG. 1, the linkmechanism 4 includes a lift link 50, a front 54, front and rear brackets55, 56, a coupling member 61 and a coupling bolt 62.

The front end of the lift link 50 is connected via a support bracket 53,to a vehicle frame 63 to be pivotable about a right and left axis. Therear end of the lift link 50 is connected via the rear bracket 56 to therear portion of the mower deck 7 to be pivotable about a right and leftaxis. At a front and rear center portion of the lift link 50, one end ofthe front link 54 is connected to be pivotable about an axis along theright and left direction and the other end of this front link 54 isconnected to the front bracket 55 extending upward from the mower deck 7to be pivotable about a right and left axis.

Downwardly of a driver's seat 57, there is supported a control arm 59operably connected to a t lever 58 to be pivotable about a right andleft axis. And, to the leading end of this control arm 59, there isfixed a coupling pin 60. The leading end of the control arm 59 isoperably coupled to a rear portion of the lift link 50 via the couplingmember 61 and the coupling bolt 62. In operation, when the control am 59is pivoted with an operation of the lift lever 58, the rear portion ofthe lift link 50 is pivoted, so that the mower unit M can be lifted andlowered via the front and rear brackets 55, 56.

As shown in FIG. 11, at the rear end of the link 50, there is fixedlyattached a band-plate like first member 51 defining a laterally orientedcoupling hole 51 a at its leading end. And, on the outer side of thisfirst member 51, and with a predetermined distance therefrom, a secondmember 52 is fixedly attached. At the rear end of this second member 52,there is formed a cutout portion 52 a, and a leading end lower portion52 c located at the lower side of this cutout portion 52 a is bent tothe inner side to be fixedly attached to the first member 51.

With the above-described construction of the rear end portion of thelift link 50, from the fore-and-aft oriented condition of the couplingbolt 62 shown in FIG. 11 (A), the leading end of this coupling bolt 62will be inserted into the coupling hole 51 a of the first member 51 fromthe outer side thereof and then, as shown in FIG. 11 (B), the couplingbolt 62 will be pivoted upward so as to be coupled with the couplingmember 61 operably coupled with the control arm 59, whereby the rearportion of the lift link 50 and the coupling member 61 can be operablycoupled with each other via the coupling bolt 62. When the coupling bolt62 shown in FIG. 11(B) is pivoted upward to be operably coupled with thecontrol arm 59 via the coupling member 61, the leading end (lower endportion) of the coupling bolt 62 is bound between the leading end of thefirst member 51 and the leading end upper portion 52 b of the secondmember 52, thus being restricted in its lateral displacement.

As a result, in comparison with e.g. a construction of coupling the rearportion of the lift link 50 with the coupling bolt 62 via a split pin(not shown), the coupling and uncoupling between the rear portion of thelift link 50 and the coupling bolt 62 can be effected easily andspeedily without needing to use a tool such as a pair of nippers (notshown) for attaching or detaching the split pin. Hence, the assemblyoperation and maintenance operation of the link mechanism 4 (themaintenance operation of the mower unit M) can be improved.

[Opening and Closing Construction of Engine Hood]

Next, with reference to FIG. 1 and FIGS. 12-14, the opening and closingconstruction of the engine hood 65 will be described. As shown in FIG.1, the hood 65 is attached to the leading end of the front frame 64extending forwardly from the vehicle body frame 63 via a pair ofbrackets 66 to be pivotally opened and closed. When the engine hood 65is pivoted forwardly, the space upwardly of the engine 5, etc. can beopened up to allow e.g. a maintenance operation of the engine 5.

As shown in FIGS. 12-14, each of the right and left brackets 66 isformed of a plate member in the form of a vertical flat plate. And, atone end thereof, there is formed an attaching portion 66 a as aninwardly bent portion. And, to this attaching portion 66 a, the enginehood 65 formed of resin is fixed by fastening. At the other end of thebracket 66 away from the side of the attaching portion 66 a, there isformed an opening 66 b having a fan shape in its side view. And, a platemember 67 is fixedly attached so as to cover this opening 66 b from theouter side, and a pin insertion hole 67 a is formed in this plate member67.

At the leading end of the front frame 64, a pin 68 projects therefrom toa lateral outer side, with the pin 68 forming a stopper flange portion68 a at its leading end. And, to the lower side of this pin 68, there isfixedly attached a fixing member 69.

As shown in FIG. 14(B), when the hood 65 is to be assembled with thefront frame 64, the pin insertion hole 67 a of the plate member 67 willbe fixed in position relative to the pin 68 and the fixing member 69juxtaposed vertically. Then, the bracket 66 will be fitted to the pin 68and the fixing member 69, whereby the pin 68 and the fixing member 69will be inserted into the pin insertion hole 67 a of the plate member67. And, then, the hood 65 will be inclined rearward, whereby the fixingmember 69 will be engaged with the opening 66 b of the bracket 66, sothat the upward displacement of the bracket 66 is restricted by the pin68 and the fixing member 69. On the other hand, when the hood 65 is tobe detached from the front frame 64, the hood 65 will be pivotedrearward to fix the pin insertion hole 67 a of the plate member 67 inposition relative to the pin 68 and the fixing member 69 verticallyjuxtaposed. Then, the engagement between the fixing member 69 and theopening 66 b of the bracket 66 will be released and then the hood 66will be pulled up.

With use of the attaching and detaching construction of the engine hood65, the maintenance operation of the engine 5 or the like can be carriedout, with detachment of the hood 65. So, that the efficiency of themaintenance operation can be improved. Moreover, in comparison with aconstruction (not shown) involving use of a bolt, a nut, or the like inthe attachment and detachment of the engine hood 65, the attachment anddetachment of the hood 65 can be carried out easily and speedily,without use of any tool so that the efficiency of the maintenanceoperation can be further improved.

As shown in FIG. 14(A), the engine hood 65 can be detached only in anintermediate (medium) condition between the fully closed condition ofthe hood 65 being fully closed and the fully open condition of the hood65 being fully opened. Therefore, in the case of e.g. a simplemaintenance operation without needing detachment of the hood 65 or anoperation for replenishing fuel to a fuel tank (not shown), suchmaintenance operation of the engine 5 or the like and fuel replenishingoperation can be done, without needing to pivot the engine hood 65 toits fully open condition to detach this hood 65. Consequently, theattachment and detachment of the engine hood 65 can be done selectively,depending on the contents of the maintenance operation. Hence, theefficiency of the maintenance operation can be improved even further.

[Lock Constructions of Parking Brake Pedal and HST Pedal]

Next, with reference to FIGS. 1 and 15, there will be described lockingconstructions of a parking blade pedal 71 and an HST pedal 72. As shownin FIG. 1, adjacent a right foot of a driver as seated at the driver'sseat 57, the parking pedal 71 and the HST pedal 72 are disposed. Theparking brake pedal 71 is operably coupled with right and left rearwheel brakes (not shown) attached to the right and left rear wheels 2.When this parking brake pedal 71 is stepped on, the right and left rearwheel brakes are activated.

The HST pedal 72 is operably coupled with an first (hydrostatic steplessspeed changing device) mounted in the transmission case 27. When the HSTpedal 72 is stepped on, a change speed operation of the riding lawnmower is effected. Incidentally, when the parking brake pedal 71 is notstepped on, the rear wheel brakes are urged to their inoperativecondition,. Whereas, when the HST pedal 72 is not stepped on, this pedalis urged to its neutral position.

As shown in FIG. 15, a bracket 71A operably coupled with the parkingbrake pedal 71 and a bracket 72A operably coupled with the HST pedal 72are supported to be pivotable independently of each other about a rightand left axis P4. Inside a lower cover 74 covering a lower portion ofthe steering wheel 73, a lock member 75 is supported to be pivotableabout a right and left axis P5. And, a control portion 75 a extends froman upper portion of this lock member 75 to the right side of the lowercover 74.

An engaging portion 71 a extends from the bracket 71A operably coupledwith the parking brake pedal 71. And, this engaging portion 71 a of theparking brake pedal 71 is disposed at a position overlapped with thelock member 75 in the front view. An engaging portion 72 a extendslaterally from the bracket 72A operably coupled with the HST pedal 72.And, this engaging portion 72 a of the HST pedal 72 is disposed at aposition overlapped with the lock member 75 in the front view. At thelower end of the lock member 75, there are formed a first cutout portion75 b engageable with an engaging portion 71 a of the parking brake pedal71 and a second cutout portion 75 c engageable with an engaging portion72 a of the HST pedal 72.

From the released condition shown in FIG. 15(A) where the lock member 75is pivoted rearward, if the parking brake pedal 71 is stepped on and thelock member 75 is pivoted forwardly, as shown in FIG. 15(B), the firstcutout portion 75 b of the lock member 75 will engage the engagingportion 71 a of the parking brake pedal 71, thus realizing a lockedcondition in which the activated condition of the rear wheel brakes withthe stepping-on operation of the parking brake pedal 71 is maintainedAnd, also, as the second cutout portion 75 c of the lock member 75engages the engaging portion 72 a of the HST pedal 72, there is realizeda locked condition which inhibits the HST pedal 72 from being activatedwith a stepping-on operation thereof

On the other hand, from the locked condition shown in FIG. 15(B) inwhich the lock member 75 has been pivoted forwardly, if the parkingbrake pedal 71 is stepped on and the lock member 75 is pivoted rearward,as shown in FIG. 15 (A), the engagement between the first cutout portion75 b of the lock member 75 and the engaging portion 71 a of the parkingbrake pedal 71 and the engagement between the second cutout portion 75 cof the lock member 75 and the engaging portion 72 a of the HST pedal 72will be released, thus realizing a released condition in whichstepping-on operations of the parking brake pedal 71 and the HST pedal72 are allowed.

As described above, by locking the parking brake pedal 71 and the HSTpedal 72 with the lock member 75, the braked condition of the rearwheels by the parking brake pedal can be maintained and at the sametime, the operation of the HST pedal 72 can be inhibited, thuspreventing erroneous operation of the HST pedal 72. As a result, whilethe parking brake pedal 71 is locked to activate the rear wheel brakes,if the HST pedal 72 is stepped on in this condition (by traveling theriding lawn mower in the activated condition of the rear wheel brakes),this would result in application of excessive force to the rear wheelbrakes and the HST, thus resulting in damage to the rear wheel brakesand HST. Such trouble as this can be effectively avoided by theabove-described construction,

Further, the above-described construction which allows locking of theparking brake pedal 71 and the HST pedal 72 with the single lock member75, in comparison with a construction which provides separate lockmembers (not shown), it is possible to avoid accidental locking failureof the lock member 75 and also to improve the controllability of thelock member 75.

First Alternative Embodiment of the Invention

In the foregoing embodiment, as the opening and closing member, theslide cover 37 is slid along the mower deck 7. However, the opening andclosing member can have a different construction as long as it can openand close the discharge outlet 7 a of the mower deck 7. For instance, adetachable type opening and closing member (not shown) can be used forclosing and opening the discharge outlet 7 a of the mower deck 7.

In the foregoing embodiment, as the guide member, the pivotal cover 30is pivotally supported to the mower deck 7, so as to be switched overbetween the raised posture and the collapsed posture. However, as longas it can be switched over in its posture between the raised posture andthe collapsed posture, the guide member can have a differentconstruction. For instance, the guide member can be configured to beswitched over in its posture, in association with attachment anddetachment thereof to and from the mower deck 7.

In the foregoing embodiment, the retaining mechanism is constructed suchthat the pivotal cover 30 can be retained in its raised posture by meansof the contact portion 31RC of the arm 31R and the support member 33.The retaining mechanism for retaining the pivotal cover 30 in its raisedposture can have a different construction. For instance, the upperportion of the mower deck 7 or the pivotal cover 30 can include aretaining member (not shown) such as a chain, a stay, etc. so that thepivotal cover 30 may be retained in its raised posture, by coupling thepivotal cover 30 in the raised posture with the mower deck 7 by means ofthis retaining member.

Second Alternative Embodiment of the Invention

In the foregoing embodiment, to the right side of the mower deck 7, theslide cover 37 and the pivotal cover 30 are attached, and the cut grassare discharged to the right outer side in the side-discharge operationmode. Instead, the slide cover 37 and the pivotal cover 30 can beattached, to the left side of the mower deck 7 so that the cut grass aredischarged to the left outer side in the side-discharge operation mode.

Third Alternative Embodiment of the Invention

In the foregoing embodiment, the riding lawn mower employs the twinblade construction in which the two rotary blades 8, 9 are mounted inthe mower unit M. However, the present invention can be applied to ariding lawn mower which employs a triple blade construction in whichthree rotary blades (not shown) are mounted in the mower unit M.

In the foregoing embodiment, the riding lawn mower is the type in whichthe mower unit M is connected to the lower bottom of the mower betweenthe front wheels 1 and the rear wheels 2 (so-called “zero turn” typemower). However, the invention can be applied to a different type oflawn mower in which the mower unit M is connected to a positionforwardly of the front wheels 1 (so-called “front mower”). Further, theinvention is not limited even to such riding lawn mowers, but can beapplied to the mower unit of a walk-behind type lawn mower as well.

Fourth Alternative Embodiment of the Invention

In this alternative embodiment, as shown in FIG. 16, the riding lawnmower has a grass collector 128 detachably attached to the rear portionof the mower. Hence, in a grass collecting operation mode to bedescribed later, cut grass cut by the rotary blades 8, 9 can betransported via a grass collecting duct 148 and a bellows duct 149 tothe grass collector 128 mounted at the rear portion of the vehicle bodyto be stored and collected therein.

From a rear portion of the riding lawn mower, a detachable attachingframe 129 extends rearwards. And, to this attaching frame 129 and fromits rear side, the grass collector 128 is detachably attached. The grasscollector 128 includes, at an upper portion thereof, a connecting port128 a to be connected with the bellows duct 149, and downwardly of thisport, a collecting portion 128 b for collecting grass is detachablyprovided. Then, by detaching the collecting portion 128 b from the grasscollector 128, cut grass collected in the collecting section 128 b canbe taken out of the vehicle.

Further, when the grass collecting duct 148 is connected to the mower M,the bellows duct 149 extendable and contractible between the rear endportion of the grass collecting duct 148 and the connecting port 128 aprovided at the upper portion of the grass collector 128 may beattached, whereby the cut grass cut by the mower M can be transported tothe grass collector 128.

As shown in FIGS. 17 and 18, the grass collecting duct 148 comprises anintegral assembly of a connecting portion 148 a to be connected with themower deck 7 located at the front portion and a pipe portion 148 bextending obliquely upward and rearward from this connecting portion 148a.

The connecting portion 148 a of the grass collecting duct 148 isconfigured so as to cover the discharge outlet 7 b of the mower deck 7in accordance with the shape of the mower deck 7. In its plan view, theconnecting portion 148 a is shaped to be curved smoothly along theoblique rearward direction along a tangent L to the outer peripheralface of the mower deck 7 at the position where the front hook 44 isprovided., whereby the cut grass cut by the rotary blades 8, 9 can besmoothly guided to the grass collector disposed rearwards.

The pipe portion 148 b of the grass collector 148 has a cylindricalshape and is formed integral with the above-described connecting portion148 a. And, this pipe portion 148 b is shaped so as to extend from therear end of the connecting port 128 a with an obliquely rearward andupward curve, toward the connecting port 128 a of the grass collector128. Referring to the shape of the rear end portion of the pipe portion148 b, this portion has an outer diameter set so as to allow gaplessengagement thereon of the bellows duct 149. These arrangements caneffectively prevent of leak of air from the connection portion betweenthe pipe portion 148 b and the bellows duct 149, which leak, ifoccurred, would result in disadvantageous reduction in the ability oftransporting the cut grass.

At the front end portion and the rear end portion of the connectingportion 148 a of the grass collecting duct 148, there are fixedlyattached a latch L and a plate 45 which are identical to a latch L and aplate 45 attached to the slide cover 37, respectively. In operation, byengaging a projection 45 a of the plate 45 into an engaging hole 44 a ofthe hook 44 rearwardly of the discharge outlet 7 b and then operatingthe latch L, the grass collecting duct 148 can be secured to the mowerdeck 7. With this construction in which the grass collecting duct 148 isdetachably attached to the mower deck 7 via the plate 45 and the latchL, in comparison with e.g. a construction in which the grass collectingduct 148 is fixed to the mower deck 7 with bolts (not shown) or thelike, the attachment and detachment of the grass collecting duct 148 canbe effected easily and speedily without needing to use any tool (notshown) for attaching or detaching the grass collecting duct 148. Hence,the efficiency of the attachment and detachment operations of the grasscollecting duct 148 can be improved.

Further, as the same latch L and the plate 45 as those used for fixingthe slide cover 37 are employed as the latch L and the plate 45 forfixing the grass collecting duct 148 to the mower deck 7, the hooks 44fixed to the mower deck 7 can be used also as fitting tools forattaching the grass collecting duct 148 to the mower deck 7.Accordingly, in comparison with a case of providing separate tools forattaching the grass collecting duct 148 to the mower deck 7, the numberof the components can be reduced and the manufacture costs can bereduced also.

With the grass collecting duct 148 having the above-describedconstruction in operation, the slide cover 37 is opened to expose thedischarge outlet 7 b of the mower deck 7 and the pivotal cover 30 ispivoted upward. Then, in this condition, the projection 45 a of theplate 45 on the rear end side of the grass collecting duct 148 isengaged into the engaging hole 44 a of the hook 44 rearwardly of thedischarge outlet 7 b, thereby to retain the rear end portion of thegrass collecting duct 148. Then, in this condition, when a pawl portionLa of the latch L at the front end of the grass collecting duct 148 isengaged with the hook 4 forwardly of the discharge outlet 7 b and then acontrol portion Lb of the latch L is collapsed rearward. With this, thegrass collecting duct 148 can be fixed to the mower deck 7.

On the rear end portion of the pipe portion 148 a constituting the grasscollecting duct 148 fixed to the mower deck 7, the front end portion ofthe bellows duct 149 is engaged and then fasted thereto with a band (notshown) and the rear end portion of the bellows duct 149 is fixed andfastened with a band (not shown) to the connecting port 128 a of thegrass collector 128. With these, the discharge outlet 7 b of the mowerdeck 7 and the connecting port 128 a of the grass collector 128 can beconnected to each other, thus realizing the grass collecting operationmode.

As shown in FIGS. 17 and FIG. 18, the pivotal cover 30 is pivoted upwardand the slide cover 37 is slid rearward to expose the outlet discharge 7b and then the grass collecting duct 148 is fixed to the dischargeoutlet 7 b. Further, the bellows duct 149 is attached between and acrossthe grass collecting duct 148 and the grass collector 128, thusrealizing the grass collecting operation mode. In this grass collectingoperation mode, the cut grass cut by the rotary blades 8, 9 can betransported to the grass collector 128 to be collected eventually in thecollecting portion 128 b provided at the lower portion of the grasscollector 128.

1. A mower unit comprising: a mower deck; a plurality of blades mountedinside said mower deck and rotatable about vertical shafts supported tosaid mower deck, said mower deck defining, on one lateral side thereof,a discharge outlet for discharging cut grass cut by the plurality ofblades; an opening and closing member configured to be moved to aclosing position for closing said discharge outlet and also to anopening position away from said discharge outlet for opening thedischarge outlet, said opening and closing member in said openingposition extends along an outer face of said mower deck; a guide memberfor guiding cut grass from said discharge outlet to a lateral outerside, said guide member being switchable in its posture between a raisedposture and a substantially horizontal posture; a retaining mechanismfor retaining said guide member in the raised posture thereof, saidretaining mechanism comprising a support member which is supported onsaid opening and closing member so as to support said guide member insaid raised posture when said discharge outlet is closed; and whereinthe mower deck has a cutting chamber for each of the plurality ofblades, each cutting chamber having an inner surface with across-section taken at a vertical plane that passes through a respectiveone of the vertical shafts of the blades, the cross-section of the innersurface of each cutting chamber being curved closer toward therespective vertical shaft in an upward direction, and wherein an innersurface of the opening and closing member has a shape that correspondsto the inner surface of a corresponding cutting chamber.
 2. The mowerunit according to claim 1, further comprising a moving mechanismconfigured to allow said opening/closing member to be moved to saidclosing position and to said opening position.
 3. The mower unitaccording to claim 2, wherein a portion of an outer peripheral face ofthe mower deck that overlaps with said opening and closing member has anarcuate shape as viewed from above; said opening and closing member hasan arcuate shape corresponding to said overlapping portion of the mowerdeck; and said moving mechanism is configured to move said opening andclosing member along the outer peripheral face of the mower deck.
 4. Themower unit according to claim 1, wherein said retaining mechanism isconfigured to retain said guide member in said raised posture when saidopening and closing member closes said discharge outlet, and to allowsaid guide member to be switched to said substantially horizontalposture when said opening and closing member opens said dischargeoutlet.
 5. The mower unit according to claim 1, wherein said opening andclosing member is configured to be pivotable about a vertical shaftsupported to said mower deck.
 6. The mower unit according to claim 1,further comprising: an arm configured to be pivotable about a verticalshaft supported to said mower deck, the arm disposed outside of themower deck, and wherein said opening and closing member is fixed to oneend of said arm to be pivotable between the closing position and theopening position.
 7. A mower unit comprising: a mower deck; plurality ofblades, each mounted inside said mower deck and rotatable about arespective vertical shaft supported to said mower deck, said mower deckdefining, on one lateral side thereof, a discharge opening fordischarging cut grass cut by the blades; an opening and closing memberconfigured to be moved to a closing position to close said dischargeopening and to an opening position away from said discharge opening toopen said discharge opening, said opening and closing member in saidopening position extends along an outer face of said mower deck; an armconfigured to be pivotable about a vertical shaft supported to saidmower deck, the arm disposed outside of the mower deck, and wherein saidopening and closing member is fixed to one end of said arm to bepivotable between the closing position and the opening position; a guidemember for guiding cut grass from said discharge opening to a lateralouter side, said guide member being switchable in its posture between araised posture and a substantially horizontal posture; and a retainingmechanism for retaining said guide member in the raised posture thereof,said retaining mechanism comprising a support member which is supportedon said opening and closing member so as to support said guide member insaid raised posture when said discharge opening is closed.
 8. The mowerunit according to claim 7, wherein the arm is further configured toallow said opening and closing member to be moved to said closingposition and to said opening position.
 9. The mower unit according toclaim 8, wherein a portion of an peripheral face of the mower deck thatoverlaps with said opening and closing member has an arcuate shape asviewed from above; said opening and closing member has an arcute shapecorresponding to said overlapping portion of the mower deck; and saidmoving mechanism is configured to move said opening and closing memberalong the outer peripheral face of the mower deck.
 10. The mower unitaccording to claim 7, wherein said retaining mechanism is configured toretain said guide member in said raised posture when said opening andclosing member closes said discharge opening, and to allow said guidemember to be switched to said substantially horizontal posture when saidopening and closing member opens said discharge opening.
 11. The mowerunit according to claim 7, wherein said opening and closing member isconfigured to be pivotable about a vertical shaft supported to saidmower deck.
 12. The mower unit according to claim 7, wherein the mowerdeck has a cutting chamber for each of the plurality of blades, eachcutting chamber having an inner surface with a cross-section taken at avertical plane that passes through a respective one of the verticalshafts of the blades, the cross-section of the inner surface of eachcutting chamber being curved closer toward the respective vertical shaftin an upward direction, and wherein an inner surface of the opening andclosing member has a shape that corresponds to the inner surface of acorresponding cutting chamber.